Hybrid drivetrains are known from series applications in motor vehicles. These hybrid drivetrains employ, for example, an electric machine, which serves as a starter for the combustion engine, as an additional or part-time solitary drive, and for recovering the kinetic energy of the motor vehicle, as a motor and generator; the electric machine being operatively connected to a battery device, which stores and emits electrical energy.
A device for reducing non-uniformities of rotation of a combustion engine is also known from German Patent No. 197 09 299 A1, where half-waves from the electric machine switched to generator operation which lie above a mean torque of the combustion engine are damped and the released energy is stored in the battery unit, and the electric machine is driven to fill out half-waves lying below a mean torque, energy being taken from the battery device. All-in-all, the charging and discharging currents which occur here at the battery device in the rhythm of the non-uniformities of rotation of the combustion engine are high, so that the battery device may not have sufficient recharging kinetics and is damaged in the course of time due to the recharging.
Furthermore, the non-uniformities of rotation, such as torsional vibrations in modern combustion engines are so high, for example, due to downsizing and the like, that traditionally employed torsional vibration dampers meet their capacity limits.